Ubuntu Security Notice 2889-2 – It was discovered that a use-after-free vulnerability existed in the AF_UNIX implementation in the Linux kernel. A local attacker could use crafted epoll_ctl calls to cause a denial of service (system crash) or expose sensitive information. It was discovered that the KVM implementation in the Linux kernel did not properly restore the values of the Programmable Interrupt Timer (PIT). A user-assisted attacker in a KVM guest could cause a denial of service in the host (system crash). Various other issues were also addressed.